The Brailsford model makes it possible to use the experimental data
obtained for the absorption of ultrasound waves to use for the
estimation of the dislocation concentration \(\Lambda _{B}\)  as well.
Really, as was shown in work [1]}, \(D_{0}\propto a^{2}\nu _{D}\)  and \((n_{0}+p_{0})\approx \left|\tan {\theta }\right|a_{s}^{-1}\) , where \(\nu _{D}\)  is the Debye frequency (\(\nu _{D}=3\times 10^{12}\)  Hz for Cd\(_{0.2}\) Hg\(_{0.8}\) Te [2]}),
\(a_{s} \)  is the interplane distance, and \(\theta \)  the angle between
the dense packing direction and the dislocation line (\(\theta \le \pi /6\) ). If we take the values \(\theta =\pi /12\)  and
\(a_{s}=a/\sqrt{3}\)  (this is the value for the \(\left\langle 110\right\rangle \)  direction [3]}), we obtain from
Eq. (REF ) that
\(\Lambda _{B}\propto \frac{1.24\,\upsilon f_{k}k\,\pi ^{3}\alpha _{m}}{Ga^{3}b^{2}g^{3}\nu _{D}Y_{m}}. \) 
